Madeleine L’Engle’s “A Wrinkle in Time,” first published in 1962, is one of the most beloved young adult novels not to have already been turned into a movie (except for a 2003 TV version that nobody, least of all L’Engle, liked), so Disney’s new big-screen adaptation has a lot riding on it. Unfortunately, it’s “The Chronicles of Narnia” all over again: a popular Christian-themed series of books whose movie version makes you wonder what everyone sees in the books.

Directed by Ava DuVernay (“Selma”) from a screenplay by Disney regular Jennifer Lee (“Wreck-It Ralph,” “Frozen”), “A Wrinkle in Time” feels like a random series of fantastical and often beautiful but still very random events. Cause and effect are not always clear; whimsical things just sort of happen. Someone turns into a giant leaf and lets the kids hop on her back to fly around like a magic carpet, then forgets about gravity and lets one of the kids fall thousands of feet to the ground, only he’s saved because Oprah tells the flowers to go catch him. Oprah is all-powerful here (as in life), but she doesn’t lift a finger herself, just bosses flowers around. Someone else only speaks in famous quotations, except when she doesn’t. The powers and forces at play are vaguely defined, nebulous in purpose. How do you access a wormhole and travel billions of light years in a few seconds? “You just have to find the right frequency and have faith in who you are.” What?!

The basic story is simple enough. Awkward, outcast teenager Meg Murry (Storm Reid) and her adopted genius 6-year-old brother, Charles Wallace (Deric McCabe), miss their father (Chris Pine), a scientist who was studying wormholes and space travel when he suddenly vanished four years ago. Now three fabulously dressed ladies — Mrs. Whatsit (Reese Witherspoon), Mrs. Who (Mindy Kaling), and Mrs. Which (Oprah Winfrey) — arrive at the Murry home pledging to use their powers as “warriors who serve the good in the universe” to help the kids find Dad. For no apparent reason, they are joined on their journey by a boy in Meg’s class, Calvin (Levi Miller), whom they barely know, while their mother (Gugu Mbatha-Raw) is left behind.

The goddess ladies have a great deal of power, though it is limited and not well explained. They whisk the kids to a foreign planet where their father spent some time, then discover he’s been imprisoned on another planet, a totally dark one. (“Dark” just means evil; the planet is well lit.) The ladies, being pure light, CANNOT teleport to a dark planet, except when they can. But then it’s only because Meg has such strong will, in that one instance, for a moment.

Most of the time — and this is the point (?) of the story — Meg is riddled with self-doubt and insecurity, which she must overcome. Yet despite “you just have to believe in yourself” being the most common of all Disney lessons, it falls flat here because of Storm Reid’s distinctly uncharismatic performance and the script’s general blandness. The conclusion is anticlimactic, again because of the vagueness of it all: They overcome evil through the power of love, activated by Meg listing her flaws to Charles Wallace. The struggles and victories are too internal to carry a movie that’s so visual.

And yet there’s a pure-hearted sweetness to everything. Words like “sincere” and “earnest” will probably appear in most of the reviews because those descriptors are as indisputably applicable as words like “fantasy” and “PG-rated” are. It’s not a matter of opinion; the movie is sincere.

The question is, sincere about what? Any overt Christianity in the book (I haven’t read it) is missing here, replaced by a flavorless “good vs. evil” philosophy and a lot of Oprah-like platitudes. (“You just have to find the right frequency and have faith in who you are” might be straight out of L’Engle, but it sounds like something Oprah would say, doesn’t it? Well-meaning but not helpful in any practical way?) It’s a nice movie that’s pretty to look at, but its niceness and prettiness are all it has going for it. Whether that’s sufficient is up to you.